Positron Emission Tomography (PET) is becoming an increasingly important imaging modality particularly for cancer diagnosis and treatment monitoring. Unfortunately, PET scanners are extremely expensive instruments; so much so, that they tend to be limited to large facilities and are almost nonexistent in rural communities or developing nations. A major cost driver for PET scanners is the scintillator crystals used to detect gamma rays emitted by the radiopharmaceuticals. Recent development of lutetium (Lu) based oxide crystals for a new generation of fast, high-resolution PET systems has made the situation even worse. These crystals are very expensive to grow and could constitute as much as 30% of the cost of a PET scanner. The objective of the current proposal is to develop low cost crystal growth of Lu-based scintillators using solid state conversion of ceramic into single crystals. Ceramics are produced in high volume resulting in low production costs per cc of yielded material. However, crystal growth is a much lower volume process (especially for oxides) with high production costs. The proposed innovation uses low cost ceramic processing methods, but then in the last step, takes advantage of unique thermodynamic processes to convert the ceramic to a single crystal. Due to the much higher volume of material produced, the processing costs of solid state growth are expected to yield Lu-based scintillators at a 50% or even 70% lower cost than conventional melt growth.